Welcome to Trouble Free Pool

We would like to welcome you to TFP, the webs leading Pool related website. We invite you to please Register to create a new account. Doing this will give you full access to the forums, where you will be able to receive personalized advice concerning your pool. We hope to see you soon!

Attempting to SLAM and want to do it right

First year taking over the pool and it has not gone as well as I hoped. I've been fighting algae problems recently, due to time away from home, and the stores have not helped me out at all. I've managed to read enough here to get started, but may still have some things wrong. The algae is currently light in color and amount.

I tested and here are the numbers:

FC - 2.5
CC - .5
AK - 130
CH - 160
CYA - 100
Ph - 7.5

Here is what I plan to do:

- Replace the water with 60% new water. Got this from the calculator.
- Brush/Vacuum as best as possible
- Get the Ph to 7.2
- Test the FC and go nuts with the bleach, checking at least twice a day and adding as needed especially in the beginning
- Backwash/Clan the filter as needed

I would then be looking for CC at .5 or lower, pass an OCLT and the water is clear.

If there is anything I'm missing or I've got something completely wrong I'd like to know before I get started. Any suggestions are welcome as well. Thanks for building the great site and am looking forward to learning how to take care of my pool properly. Sorry for the length, wanted to make sure I was thorough. Thanks!

Re: Attempting to SLAM and want to do it right

Thanks for the quick reply!

I meant to put .5 for the CC. sorry for the confusion. I've fixed it now.

Another question, It has been a very mild summer and is already almost time to close up the pool for the winter sometime next month. Is it worth slamming or should I just close it and open it with a SLAM next year or will it make the problem worse?

Re: Attempting to SLAM and want to do it right

Good! You have your own test kit. That is a good start!

I would SLAM it just because I THINK it would make it easier to open next Spring. I am not sure if there is any truth in my thoughts but...................I would have to at least try to close it clear and clean.

Attempting to SLAM and want to do it right

I think it would be a good ideas to SLAM before closing. The algae will live on until the water temp drops below 60F and so you'll be better off in the spring if you kill it all now. Otherwise it grows and dies over winter and the water is just a soup of dead algae and organics which can stick to and stain your liner.

Re: Attempting to SLAM and want to do it right

Sorry for not updating sooner, having enough problems finding time to make sure I test the pool enough during the process. I have kept notes throughout and believe I may be done or close to it. Here is everything I have recorded. It's possible I forgot to write one down but the chemical amounts were always correct to take it to the required Shock FC level.

The first thing I did was drain the pool and replace at least 60% of the water with new water.

Re: Attempting to SLAM and want to do it right

Well, normally you should record your starting pressure and then backwash when the filter pressure gauge reads 25% over START pressure. Most filter gauges have a rotatable plastic face ring with the words "START" and "SERVICE" printed on it so you can mark your starting point.

When SLAMing, I typically backwash my DE filter when I hit 20% over nominal because your killing so much algae and generating so much waste that it just works better.

Re: Attempting to SLAM and want to do it right

Anytime I have looked at the filter it is between 20-25%. Before and during the slam. It has never changed unless I backwash/waste/rinse whatever. It drops but then when set to filter it's back up to the 20s.

Attempting to SLAM and want to do it right

What's the actual PSI reading when you start?

Depending on the age of your filter, the gauge could be bad and in need of replacement. You can buy cheap ones from the pool store that read +\- 1 psi or TFTestKits.net sells better ones that read +\- 0.5 psi